Bag making apparatus



- Elnite States 1,383,234 12/1964 France atent Kurt Herbert Reissner Inventor Lengerich, Germany Appl. No. 757,175 Filed July 29, 1968 Patented 0ct. 13, 1970 Assignee Windmoller & l-lolscher K. G.

Lengerich, Westphalia, Germany Priority July 29, 1967 Germany 1,61 1,693

BAG MAKllNG APPARATUS 1 Claim, 2 Drawing Figs.

US. Cl 93/27, 93/21 Int. Cl B3lb 1/00 Field ofScarch 93/21, 22, 23,25,26.'27,2 9

References Cited FOREIGN PATENTS Primary Etqminer-Be rnard Stickney Arror ney spencerandKaye 7 ABSTRACT: Bag making apparatus comprising a cylinder for making bag bottoms comprising at least two supporting means rotatable about a common shaft with respect to each other and adapted to be fixed in each position so obtained, one of said supporting means carrying-seen in the direction of travel of the workpiecefront means for gripping the side edges of the workpiece and means for folding the front bottom fold line, the other of said supporting means carrying back gripping means and means for folding the back bottom fold line, and bridging means provided between said two folding means and shaped according to the circumference of said bottom making cylinder, the improvement comprising two rakes each comprising teeth facing and interengaging each other and adapted to serve as said bridging means, wherein one of said rakes is provided on one of said supporting means behind said front folding means and the other ofsaid rakes is provided on one of said supporting means in front of said back folding means.

Patented Oct. 13, 1970 3 v 3,533,330

INVENTOR Kurt Herbert REISSNER ATTORNEYS BAG MAKING APPARATUS The present invention relates to a bag making apparatus 7 comprising a cylinder for making the bag bottoms. Said the workpiece front means for gripping the side edges of the workpiece and means for folding the front bottom fold line, while the other carries the back gripping means and the means for folding the back bottom fold line, a bridge being provided between said two folding means which is shaped according to the circumference of said bottom making cylinder.

The provision of a bridge for covering the free space between the two folding means is necessary for assuring a clean making of the fold lines, in order that the workpiece has the required supporting face. On the other hand, the adhesive for closing the bottom is brought onto the opened bottom in a further working step, while the workpiece is still held on the bottom making cylinder, so that, for applying the adhesive satisfactorily, the support by said bridge is as well necessary.

In known apparatus of the kind described a'plurality of inserts corresponding to the various bottom widths are to be kept in stock to serve as bridging members, which inserts must be secured to the basic body of the bottom making cylinder or to said two supporting means by bolts. When changing the bottom width of the bags to be manufactured, this means additional work of resetting the apparatus which reduces the operating time and hence the output of the machine.

It is an object of the invention to simplify resetting of the apparatus in order to increase its output.

Broadly, this aim is achieved by providing two rakes to serve as a bridging member, one of said rakes being mounted on a supporting means behind the front folding means and the other being mounted on a supporting means in front of the back folding means, and wherein the teeth of said two rakes are facing each other in such a way that they interengage. In such a manner it is obtained that onchanging the position of one of the two supporting means the space between the latter 7 always remains bridged. The length of the teeth should be taken in accordance with the largest and smallest bottom widths to be manufactured. In case of the smallest bottom width the teeth may only just touch the traverse of the opposite rake, while in case of the largest bottom width the top ends of the two opposing rows of teeth should at least be on a common line, in order to avoid any free space. By providing each rake with a sufficient number of teeth the tooth spaces become so small that, when the tooth spaces are free during the manufacture of large bottoms, pressing or hanging of the workpiece through between the teeth cannot occuron account of the small distance between the teeth. In this way the required support of the workpieces is always guaranteed.

The foregoing and other objects, features and advantages of, the present invention will be apparent from a consideration of the following specification taken in connection with the accompanying drawings which show a preferred embodiment of the invention.

In the drawings;

FIG. 1 is a side elevation of the bottom forming part of the bottom making cylinder; and

FIG. 2 is a developed view of the part of the bottom making cylinder of FIG. 1. i

The bottom making cylinder comprises supporting members l, 2 and 3. The supporting member I is unrotatably secured to a shaft 19 and carries a front pair of grippers 4 for I gripping the side edges of the workpiece, pliers 5 for folding the front bottom fold line, and a rake 6 which has teeth 7. The supporting member 2 carries a second rake 8 the teeth 9 of which interengage the teeth 7 of the rake 6, pliers l0 for'folding the back bottom fold line which are arranged behind the rake 8, a back pair of grippers 11 for gripping the side edges of the workpiece, and a cylinder jacket piece 12. Supporting member 2 is rotatable about shaft 19 and can be secured to a ring 13 having slots 14 b means of bolts 15 for positioning member 2 according to t e desired bottom width. Ring 13 is While I have shown and described a preferred embodiment of my invention, it will be understood that modif cations and variations will be apparent to those skilled in the art and such modifications and changes may be made without departing from the essence of the invention. It is intended to cover herein all such modifications and changes as come within the true scope and spirit of the claim.

I claim:

1. Bag making apparatuscomprising a cylinder for making bag bottoms comprising at least two supporting means rotatable about a common shaft with respect to each other and adapted to be fixed in each position so obtained, one of said supporting means carrying seen in the direction of travel of the workpiece front means for gripping the side edges of the workpiece and means for folding the front bottom fold line, the otherof said supporting means carrying back gripping means and means for folding the back bottom fold line, and

' bridging means provided between said two folding means and folding means and the other of said rakes is provided on one of saidsupporting means in front of said back folding means. 

